Summon
Free Summon can be perform 5 times a day, with 10-minute cooldown. A Gold Summon can be perform every 46 hours.
Spend Gold to purchase a Jade Egg, and gain a chance to summon hero, which has a chance to gain heroes with quality 11, 12 or 13.
Purchase 10 Jade Eggs in one shot, gain 10 chance to summon hero and at least a golden hero.